Bomb



March 22, 1938. J B, McGAY ET AL 2,112,174

BOMB

Filed Oct. 26, 1955 mm: mm

INVENTOEZS John B. 9 ga l v Cjeor ge f./\//'(: 0150/? BY My 49 FIG. 5ATTORNEY.

Patented Mar. 22, 1938 PATENT OFFICE BOMB , John B-MOGSY and George E.Nicholson, Tulsa,

kla., assignors, by mesne assignments, to E. I. du Pont de Nemours &Company, a corporation of Delaware Application October 26, 1935, SerialNo. 46,874 23 Claims. (Cl. 102-41 This invention relates to bombs foruse in shooting oil wells, and more particularly to bombs provided withtiming mechanism for controlling the explosion of the charge.

One object of the invention is to provide a bomb embodying ignitingmeans fired by a firing pin, a hammer for strikingthe pin, which hammeris held cocked when the bomb is set, and

driven means for controlling and releasing the hammer, such means beingadjustable to control the elapsed time between the setting of thereleasing means and the release of the hammer. A further object is toprovide a bomb wherein the releasing means is carriedupon a rod drivenlengthwise by clockwork and releases the hammer in its travel, theinitial position of the rod being adjustable for control of the time ofrelease.

A further object is to provide a bomb wherein the releasing means alsoserves as a carrier for the firing pin. Another object is to provide abomb wherein a plurality of firing pins are simultaneously struck by thehammer and a corresponding plurality of detonating chargessimultaneously ignited. Another object is to provide a bomb wherein,should the hammer be accidentally released, the travel of the membercarrying the firing pin is stopped and accidental firing of the bombprevented. Other objects will appear hereinafter. I

These objects may be accomplished by the bomb illustrated in theaccompanying drawing, and without limiting the invention thereto, it isdescribed with more particular reference thereto.

Inthe drawing:-

Figure 1 is a longitudinal diametrical crosssectional view of the bomb(thus giving a rear view of the timing and firing mechanism shown inface view in Figure 2), -a portion of the lower 1 portion of the casebeing omitted; Figure 2 is an elevation, partially in section looking inthe direction of the arrow a in Figures and 7, of the timing and firingmechanism; Figure 3 is an elevational cross-sectional view throughthecombined carrier and controller slide showing the firing pins and themounting therefor; .Fig-

- ure 4 is a cross-sectional view through the slide taken substantiallyon the line 4-4 of Figure 3, showing the pin-holding spring; Figure 5 isa cross-sectional view substantially on the line 5-5 of Figure 2; Figure6 is an elevational fragmentary section through the two slides with thefiring pins omitted; Figure '7 is a sectional view taken substantiallyon the line 1-1 of Figure2; Figure 8 is a view taken substantially atthe line 8 -8 of Figure 9 and showing the bottom plate of the frame, theside bars being omitted; and Figure 9 is an elevational cross-sectionalview taken substantially on the line 9-9 of Figure 8. It is to beunderstood that various figures are 5 to difierent scales. The bomb maycomprise two complete sets of timing and firing mechanisms arranged backto back, as is indicated in Figures 5 to 8, the two sets being arrangedto operate each on its own igniting devices and all the igniting devicesbeing grouped together at the firing ends of the sets. Since, however, adescription of one set will sufiice for both, for the most part but oneset'is described in detail.

Referring to the illustrated bomb, in general the bombcomprises the caseI within which are received the firing and timing mechanism 2, theigniting means 3, the detonating means 4.

and the explosive charge 5. The explosion of the charge 5, that is, theexplosion of the bomb,

explodes the main charge for shooting the well and which is placed inthe well along with the bomb.

The timing and firing mechanism comprises the spring-driven hammer 6,the pivoted leverlike latches or triggers l, 1, the crosshead orcarrier-controller 8 travelling between the. side bars or guides 9 andcarrying the firing pins l0, and on the rod II. The rod II is drivendownward (in the drawing) by the clockwork II to carry the crossheadclose to the igniter 3, in which position the hammer can strike the pinsI II and move them .in the'crosshead to set off the igniter.

The crosshead 8 also serves as a stop to prevent the movement of thelatches I to release the hammer, but when the crosshead reaches firingposition it passes beyond the lower ends of the latches and releasesthem, whereupon the ham 40 mer, urged by its spring l3, trips thelatches, descends, and strikes the firing pins.

The rod ll carrying the controller 8 may be adjusted up or downindependently of the clock mechanism, to thus initiallyplace thecontroller at any selected distance above the lower ends of the latchlevers, and the clock mechanism then drives the rod and controller overthe path extending from .the selected position to latch-releasingposition. Evidently the length of this path represents the elapsed timebetween the setting of the mechanism and the release of the hammer andconsequent firing. The guides or slideways 9 may be provided with a timescale in hours and fractions thereof, if desired, as indicated at. H.

The time mechanism, here exemplified by the clockwork l2, convenientlykey wound, may be of any desired character adapted to the ends soughtand, as indicated just above in reference to the time scale, isdesirably such as to ensure a controlled rate of travel for thecontroller 8, the details thereof not forming a primary feature of thepresent invention. Of particular present significance, the clockworkpresents the final driving pinion l5 engaging the circular involutetooth rack It, provided with friction retainer H to prevent the rod fromturning under the driving pressure of the pinion on the rack. The rackis provided on the rod ll. With this arrangement the rod can be adjustedup or down as before mentioned, by turning it, as with ascrew-driverlike tool engaged in a slot 23 in the lower end of the rod,the rod screwing up or down through the teeth of the pinion. The pinionthereafter drives the rod downward by its engagement with the rack. Bychanging the ratio between the pinion and .the rack, as by changing todifferent sized pinions, any desired maximum time limit for the bomb maybe provided.

.The hammer 6 is mounted slidably upon the rod II, which passes freelytherethrough, and the hammer is actuated by the coil spring [3 heldunder compression between the hammer and the structural plate It.Desirably the hammer passes through, and when in its set" position restsin, a guide I! fixed to the side bars or guides 9. Also a sleeve 20,here shown as a short extension of the hammer 6, may be used within thespring to brace the same against under cramping or buckling in the eventthat the spring is of considerably larger diameter than the rod ll.Also, if desired, the sleeve 5| that houses the upper end of the rod II,as hereafter described, may be extended somewhat below the plate l8, tobe received within the spring for the support thereof.

The hammer 6 is provided with a shoulder 2| with a peripheral bevel 2|against which the rounded end 22 of the short arm of latch lever Irests. These are of such cooperating contours that the hammer, urgeddownward by the spring It, tends to, push the upper end of the lever(pivoted at 23) away from the shoulder 2| and release the hammer. (Theangle of the bevel 2 I is such that the power required to hold the latchin place is very small.) This action is normally prevented by thecrosshead 3 which prevents movement of the lever by contact with thelonger arm thereof, until the crossheadpasses beyond the end 24,whereupon the pressure of the hammer can move the short arm of the leveroutward and the hammer is released. with this arrangement, as the clockruns down, and the crosshead and firing pins approach the igniters, theleverage ratio of the distances of crosshead to pivot 23] and pivot toend 22 constantly increases, thereby decreasing the pressure of thecrosshead against the latch and decreasing the amount of clock powerrequired to drive the crosshead.

The slide 3 comprises the lever-contacting plate 25 and the cam plate 26connected by the back plate 26. As shown in Figure 3 the end of the rodII is reduced in diameter to provide shoulder 21 and threaded extension23. A member 23 is screwed fast upon the extension 23 to hold the slideupon the rod. The rod and its member 23 are rotatable in the slide.Between the plate 25 and the shoulder 3| of the member 23 is mounted thedished spring plate or friction retainer 11.

7 project.

The pressure thereof against the shoulder 33 prevents the turning of therod under the driving pressure of the pinion l5, but permits manualturning of the rod to adjust the travel of the rod and crosshead. Theslide 8 is prevented from rotation by the notched ends 25 of the plate25, and the rear jaws of the notches 32 hereafter referred to,overlapping the edges of the guides 9.

The firing pins H) are mounted in the crosshead for movement therein,both longitudinally and sidewise, the plate 25 being provided with theholes 3|, 3| surrounding the shanks of the pins with some clearance, andthe plate 26 having notches 32, 32, in which the pins normally rest. Aspring 33 normally holds the pins lightly invertical position.

Each pin is provided with a sharp edged peripheral skirt 34 and with aperipheral downwardly tapering cam 35. This arrangement provides asafety feature. If the hammer 6 is accidently released before thecrosshead has descended far enough to bring the pins into proper andintended position (to be described below) the hammer in striking thepins drives them so far through the notches 32 that the taperedprojections 35 cam on the edges of the notches 32 and forcibly cant thepins outward, the loose fit in the holes 3|, the'open notches 32 and thelight spring 33 permitting this. This causes the edges of the skirts 34to bite into the sides of the guides 9 and prevent further downwardmovement of the crosshead, wherefor the pins in are prevented fromreaching firing position and firing the bomb.

The bottom plate 36, mounted adjacent the ends of the guides 9, isprovided with trueing holes 31 to receive the pins illat the end of thestroke of the crosshead, and properly present the pins in firingposition before the igniting means 3, that is, specifically in thearrangement here shown, the caps 38 of the cartridges 39. As will beunderstood, the parts are so proportioned and arranged that thecrosshead reaches a position to properly present the pins before thecaps 33 by, or before, the moment when the crosshead frees the lowerends of the levers 1 and releases the hammer. Also, of course, thearrangement is such that the hammer can give the full neces-' saryfiring stroke to the pins without driving them so far that the earns 35come into action and bind the pins against the sides of the holes 31.

In addition to the holes 31 for the firing pins, the plate 36, indevices such as the illustrated one wherein it is intended to turn therack bar H with a screw-driver-like tool, is provided with a hole 40 inalignment with the end of the member 29. Through this the tool forengagement with the slot 29' may be introduced. (See Figures 5 and 8,the slot 29" which lies above the hole 43 being indicated by phantomlines in Figure 8.) The bottom plate 36 may be assembled with the guides3 in any desired manner. In the present instance it is slipped tightlyover the extensions 4|, ll of the side bars 9, 3. These extensionsreceive betweenthem the holder, designated generally as 42, for thecartridges 3!.

The holder 42 comprises head 43 detachably received between the ends IIand held assembled therewith by the removable pin 44. The head receivesthe cartridges 39 in holes 45, the heads of the cartridges resting onthe upper face of the head. The head is provided with a cylindricalskirt 45 into the interior of which the cartridges As detonating means 4in the present instance, the cartridges have blasting caps assembledthereon, a cap with fuse removed, being igniter, it having been foundthat the usual explosive charge of the cartridge is not necessary forpresent purposes. assembly of timer, cartridges, etc. is placed above asmuch eirplosive charge, carried in the lower portion of the case, asdesired; and if desired the explosive charge may be extended into theskirt l5 and packed around the blasting caps. (It will be evident theremoval of the holder 42 gives ready access to the screw driver holeIii).

With this arrangement, the separable holder 42,the igniter, and otherelements immediately associated with the unit 42, may be kept entirelyseparated from the remaining parts, rnore par, ticularly the hammer andfiring pins, until such time as the loading is entirely completed. Thus,

- the hazard of handling is greatly'decreased. The

- tion, one mechanism may be set to operate a short time after theother, and thus even through one holder 42 is then finally assembledwith the timer and immediately related parts by introducing the preparedunit 42 between'the ends ll and inserting the crosspin 44. As a furthersafety feature,

a removable crosspin 41 is provided which when in place forms a positivestop preventing the crosshead descending sumciently to release thelevers or to place the firing pins in firing position. 1

As will be evident, when the holder 42 is in position below the plate36, access to the hole I for the introduction of the tool to adjust therack bar II is prevented. Thus, afterthe mechanism has been set for thepredetermined time, and the carrier has been fastened in place, anychanging of the flring time is precluded, unless the holder, carryingthe caps and so forthwith it, is first completely removed.

The timing assembly may, if desired, be provided with a handle 48. Alsoa cover 49, say a sheet of transparent cellulosic plastic, may beprovided as a closure for the clockwork. This may be wrapped about thestructure formed by the plate l8, top plate 50, side bars 9, 9 andsleeve or sleeves 5| housing the rack bar or rack bars II, and cementedalong its edges. (The sleeves 5i have apertures 5| permitting engagementof the rack and pinion).

It is to be noted that with the provision of' two firing pins, operatedby the single timing mechanism, and two cartridges and two blasting capsthere are provided two complete operating trains from the timer to thecharge. Thus the possible failure to function of one train is unlikelyto re-' suit in a misfire. Furthermore, as herebefore mentioned, thetiming and firing mechanism may be completely duplicated in the bomb,much of this duplication being omitted in the drawing for simplicity,but being indicated in Figures 5 to 8, and the cartridge holder beingshown as capable of the mechanisms fails to fire both of the cartridgesarranged for it, the possibility that the.

other mechanism will not fire either of its cartridges is so far remotethat the possibility of the bomb not firing is practically whollyeliminated.

While in the illustrated bomb,"a pair of latches I is provided, and apair of pins or devices I!) for biting into the guides, as is preferablefor safety,

it will be understood that but one latch and/or but one biting devicemay be used if desired.

The preferably metal casing of the bomb is, in

In assembling the bomb, the

With this duplicathe illustrated device, of cylindrical form with endclosures designated generally as 52 and 53. The top 52 comprises closureproper 54 shouldered at 55 to cooperate with the corresponding shoulder56 of the body of the casing, a gasket 51 of rubber or the like beinginserted between the shoulders.

The closure proper 54 carries a, stud 58 to reserted' in the open end ofthe case, and anchored in place by the wire 53, turning the nut 59 willforce the plates 54 and 5| apart and thus force the plate into tight fitupon the gasket 51. Conveniently the threads within the nut, and theflange 52, are provided by an interior threaded member 65 provided withthe flange and (after the plate 6| has been mounted thereon)drivefitted-and-pinned into the center hole of the nut. For the bottomclosure 53, the nut may be omitted and the edge of the casing spuntightly down upon the edge of the pressure plate 5i, to hold the closure54' against the gasket 51, the wire split ring beingomitted.

The casing is desirably I of aluminum alloy.- This alloy is preferablyof substantially the composition aluminum 97.9, magnesium 0.9, silicon1.2, per cent.

The various mechanical parts of the bomb are desirably of any suitablemetal or metals. Care ceive theg ut 59 rotated by the handle or bail 60.

should be taken of course to so mate the metals of the pins Ill and theguides 8 that the pins can properly bite into the guides. -Should it bedesired not to embody the stop feature provided by the illustrated pinsill the cams 35 may be omitted, and the skirts, if desired, given theform of simple'fianges to prevent theloss of the pins through theapertures 3i and 32. Furthermore, but a single firing pin and ignitingdevice may be used if it is not desired to embody the present doublefiring train features.

The operation of the bomb will be evident from the above description. Inbrief, with the crosshead in lowered position the hammer is pulled back,the latches placed in looking position and the crosshead moved up tohold the lower end of the levers spread, the rod and crosshead beinscrewed upward to the desired time position. If the bomb embodies twotimers, hammers, etc.) (the clockwork for a second timer being indicatedat I2 in Figure 2) the other timer is also set and the pin 41 (arrangedto intersect the paths of both crossheads when two are used) inserted.The

prepared carrier 43 is now attached. When the and the main charge forblowing the well, may be if desired, say dynamite packed about theblasting caps for the charge of the bomb and nitroglycerin for the maincharge.

While the bomb has, for definiteness, been more particularly describedin connection with its use for the shooting of oil wells, it will beunderstood that bombs of the present invention are of use in variousother connections, and

therefore such bombs are not confined in their uses to the shooting ofoil wells.

It is apparentthat many widely different embodiments of this inventionmay be made without departing from the spirit and scope thereof and,therefore, it is not intended to be limited except as indicated in theappended claims.

We claim: g

1. In a bomb, in combination, a releasable element adapted to operate anigniting device, means for actuating said element, releasable means forholding said element cocked, such releasable means being movable intoreleasing position under the urge of said element but being normallyheld in cocked position by the hereafter named travelling controller andreleased thereby upon the controller reaching releasing position on itsstroke, a travelling controller, time mechanism for driving saidcontroller from initial position to releasing position, and means indriving relation to said controller and in driven connection with saidtime mechanism and adjustable in respect to said time mechanism, wherebythe controller may be adjusted to different selected initial positionsto change the length of its stroke from initial position to releasingposition, whereby the firing time of the bomb is controlled by thepredetermined and adjustable length of the path of travel of thecontroller while in position to hold said releasable means in cockedposition.

2. In a bomb, in. combination, releasable igniter-operating means, meansfor actuating said igniter-operating means, releasable locking means forholding said igniter-operating means cocked, a travellingcarrier-controller normally holding said locking means in cockedposition, and releasing said locking means upon the carrier-controllerreaching releasing position in its stroke, said carrier-controller beingmounted for travel backward and forward before the hereafter namedigniter, an igniter, a device operatively relating saidigniter-operating means and said igniter for operation of said igniterby said igniter-operating means and carried by said carrier-controller,for presentation in operating relation to said igniter upon the forwardstroke of said carrier-controller, time mechanism for driving saidcarrier-controller forwardly toward said igniter and into position torelease said locking means, and to present said device inigniter-operating position with respect to said igniter, and meanswhereby said carrier-controller may be adjusted backward from theigniter to selected position, thus to change the length of the timedtravel of the carrier-controller, and hence the firing time,

3. In a bomb, in combination, an igniter firable by a firing pin, afiring pin carrier located before said igniter and movable toward andfrom the same, a firing pin carried by said carrier, a hammer forstriking said pin, means for actuating said hammer, releasable means forholding said hammer cocked and held in cocked position by said pincarrier during its travel toward said igniter and released by saidcarrier adjacent the end of the stroke thereof, said carrier beingadjustable away from said igniter to initial stroke position, and timemechanism for driving said carrier from said position tohammer-releasing position.

4. In a bomb, in combination, a hammer, means for actuating said hammer,a latch for holding the hammer cocked, a travelling carriercontrollernormally holding said latch in cocked position "and releasing said latchupon the carrier-controller reaching releasing position in its stroke,said carrier-controller being mounted for travel backward'and forwardbefore the hereafter named igniter, an igniter, a firing pin for saidigniter carried on said carrier-controller for presentation before saidigniter upon the forward stroke of said carrier-controller, timemechanism for driving said carrier-controller forwardly toward saidigniter and into latch-releasing position, the parts being so relatedthat such releasing position and the position of presentation of thefiring pin in igniter-operating relation to said igniter aresubstantially coincident, and means whereby said carrier-controller maybe adjusted backward from the igniter to selected position to change thelength of the time travel ofthe carrier-controller from initial positionto latch-releasing and firing-pin-presentation position.

5. In a bomb, in combination, an igniter firable by a firing pin, afiring pin movably mounted independently of the hereafter named hammerfor movement toward and from said igniter, a hammer for striking saidpin, means for actuating said hammer, releasable means for holding saidhammer cocked, such releasable means being movable into releasingposition under the urge of said hammer but being normally held in cockedposition by the hereafter named travelling controller and releasedthereby adjacent the end of the stroke thereof, a travelling controller,said controller being adjustable to initial stroke position, whereby thefiring time of the bomb is controlled by the predetermined andadjustable length of the path of travel of the controller while inposition to hold said releasable means in cocked position, there beingconnections between said pin and said time mechanism whereby theposition of said pin with respect to said igniter is determined by saidtime mechanism independently of said hammer, and time mechanism fordriving said controller from said position to hammer-releasing position.I

6. In a bomb, in combination, an igniter firable by a firing pin, afiring pin movably mounted independently of the hereafter named hammerfor movement toward and from said igniter, a hammer for striking saidpin, means for actuating said hammer, releasable means for holding saidhammer cocked, such releasable means being movable into releasingposition under the urge of said hammer but being normally held in cockedposition by the hereafter named travelling controller and releasedthereby adjacent the end of the stroke thereof, a travelling controller,said controller being adjustable to initial stroke position, whereby thefiring time of the bomb is controlled by the predetermined andadjustable length of the path of travel of the controller while inposition to hold said releasable means in cocked position, there beingconnections between said pin and said controller whereby the position ofsaid pin with respect to said igniter is determined by said controllerindependently of said hammer, and time mechanism for driving saidcontroller from said position to hammer-releasing position.

7. In a bomb, in combination, an igniting device, a releasable elementfor operating the same, means for actuating said element, releasablemeans for holding said releasable element cocked, a travelling devicefor holding said means in cocked position, a member for cooperativelyrelating said element and said igniting device for operation of saidigniting device by said element,

said travelling device holding said releasing means in cocked positionduring its travel and ultimately releasing such means, said travellingdevice presenting said cooperative member in cooperative relation withsaid igniting device when such ultimate releasing position is reached,and said travelling device being located to itself serve as a stop forsaid releasable element upon 00- casion, and means whereby travel ofsaid device is stopped should said releasable element be prematurelyreleased, thusto stop said releasable element, prior to said devicepresenting said cooperative member in cooperative relation to saidigniter.

8. In a bomb, in combination, a releasable element adapted to operatearr: igniting device, means for actuating said element, releasable meansfor holding said element cocked, such releasable means being movableinto releasing position under the urge of said element but bein normallyheld in cocked position by the hereafter named travelling controller andreleased thereby upon the controller reachingreleasing position on itsstroke, a travelling controller time mechanism for driving saidcontroller from initial position to releasing position, and meanswhereby the controller may be adjusted to difierent selected initialpositions to change the length of its stroke from initial position toreleasing position, whereby the firing time of the bomb is controlled bythe predetermined and adjustable length of the path of travel of thecontroller while in position to hold said releasable means in cockedposition, such means comprising a rack in driving relation to saidcontroller and in driven connection with a pinion of said timemechanism, said rack being shiftable past said pinion to select itsinitial position with respect thereto.

9. In a bomb, in combination,a releasable element adapted to operate anigniting device, means for actuating said element, releasable means forHolding said element cocked, such releasable means being movable intoreleasing position under the urge of said element but being normallyheld in cocked position by the hereafter named I travelling controllerand released thereby upon the controller reaching releasing position onits stroke, a travelling controllertime mechanism for driving saidcontroller from initial position to releasing position, and meanswhereby the controller may be adjusted to different selected initialpositions to change the length of its stroke from initial position toreleasing position, whereby the firing time of the bomb is controlled bythe predetermined and adjustable length of the path of travel of thecontroller while in position to hold said releasable means in cockedposition, such means comprising a rack in' driving relation to saidcontroller and in driven connection with a pinion of said timemechanism, said rack having circular involute teeth in mesh with saidpinion whereby said rack may be turned through the teeth of the pinionto select the racks initial position with respect to said pinion.

10. In a bomb, in combination, a releasable element adapted to operatean igniting device, means for actuating said element, releasable meansfor holding said element cocked, such releasable means being movableinto releasing position under the urge of said element but beingnormally held. in cocked position by the hereafter named travellingcontroller and released thereby upon the controller-reaching releasingposition on its stroke, a travelling controller time mechanism fordriving said controller from initial position to releasing position, andmeans whereby the controller may be adjusted to different selectedinitial positions to change the length of its stroke from initialposition to releasing position, whereby the firing time of the bomb iscontrolled by the predetermined and adjustable length of the path oftravel of the controller ,through the teeth of the pinion to select theracks initial position with respect to said pinion,-

and retaining means to prevent the rotation of said rack and turningunder the driving pressure of the pinion.

11. In a bomb, in combination, an igniting device, releasable means foroperating the same, means for actuating said operating means, aslideway, a controller slide mounted to travel therealong, a firing pincarried by said controller slide for cooperation between said releasablemeans and said igniting device, a trigger member mounted adjacent saidslideway and extending therealong for engagement with said controllerslide and normally serving to hold said releasable means cocked when inengagement with said controller slide, said controller slide beingmovable, in its travel forward towards said igniting device to'aposition out of engagement driving said controller slide along saidslideway to its out-oi-engagement position with respect to said triggermember, thereby to release said means for operating the igniter.

12. In a bomb, in combination, an igniting device, means for operatingthe same and including a driven hammer and means for actuating saidhammer, a slideway, a controller slide mounted to travel therealong, afiring pin carried by said controller slide for cooperation between saidhammer and said igniting device, a trigger lever mounted adjacent saidslideway and having one arm in restraining relation to said hammer andthe other arm'extending along said slideway for engagement with saidcon'troller slide and normally serving to hold said hammer cocked, whenin engagement with said controller slide, said controller slide beingmovable, in its travel forward towards said igniting device to aposition out of engagement with said lever to release the same, and saidcontroller slide being adjustable to initial stroke position, and timemechanism for driving said controller slide along said slideway to itsout-of-engagement position with respect to said lever member thereby torelease saidhammer for operating the igniter.

13. A bomb as set forth in claim 12.wherein the arms of the lever are ofunequal length and the short arm is in restraining relation to thehammer.

14. A bomb as set forth in claim 12 wherein the arms of the lever are ofunequal length and the short arm is in restraining relation to thehammer and the hammer and such arm are in contact and so related thatthe power required Ill) in which said carrier is mounted for traveltherealong, a hammer for longitudinally moving said pin on said carrierto operate said igniter, said carrier being so located with respect tosaid hammer as to serve as a stop for said hammer upon occasion, meansfor actuating said hammer, and means whereby upon movement of said pinin said carrier greater than that required for operation of saidigniter, said carrier is locked in said guideway and prevents travel ofsaid hammer.

16. In a bomb, in combination, an igniter operable by a firing pin, afiring pin carrier, a firing pin mounted on said carrier forlongitudinal travel thereon, a guideway for said carrier, and in whichsaid carrier is mounted for travel therealong, a hammer forlongitudinally moving said pin on said carrier to operate said igniter,said carrier being so located with respect to said hammer as to serve asa stop for said hammer upon occasion, means for actuating said hammer,said pin and carrier being cooperatively related to provide for axialtravel of said pin suflicient to actuate said igniter, and for cantedtravel upon passing the limit of axial travel, said pin having means forforcibly engaging said guideway in the 18. In a bomb, in combination, anigniting device, adjustable means for the timed operation of said deviceand including a rack bar rotatable to adjust said means for the selectedtiming of the bomb, and means for supporting said device and including aplate arranged crosswise of the end of said rack bar when saidadjustable means and said device-supporting means are assembled, thus toprevent access to the end of said rack bar by a tool for the rotation ofsaid rack bar.

19. In a bomb, in combination, a casing interiorly shouldered andprovided above said shoulder and, spaced therefrom, with an interiorcircumferential retaining groove, an explosive charge received in saidcasing, a timed firing mechanism received in said casing, and aremovable closure for said casing, said closure comprising a closureproper received upon said shoulder, a pressure plate arranged below saidretaining groove, means to force said closure proper g and said plateapart thus to force said closure said end, with the land of saidshoulder facing said end and the interior surface of said casing abovesaid shoulder of a character permitting crowding of the hereinafternamed closure element toward the hereinafter named gasket by externalfluid pressure upon such element, an explosive charge received in saidcasing, a timed firing mechanism received in said casing, a closureelement received upon said shoulder and thus located for exposure toexterior pressure, such closure element and the hereafter named gasketbeing peripherally encompassed by said casing above said shoulder, agasket received upon said shoulder between the same and said element,and means exterior of said closure element and thus accessible from theexterior of said casing, cooperable with said closure element forcrowding said closure element toward said gasket and shoulder.

21. A bomb casing interiorly shouldered and provided above said shoulderand spaced therefrom with an interior circumferential retaining groove,and a removable closure for said casing, said closure comprising aclosure proper received upon said shoulder, a pressure plate arrangedbelow said retaining groove, means to force said closure proper and saidplate apart thus to force said closure toward said shoulder, and aretaining ring received in said groove and backing said pressure plate.

22. A bomb casing having an open end and interiorly shouldered adjacentsaid end, with the land of said shoulder facing said end and theinterior surface of said casing above said shoulder of a characterpermitting crowding of the hereinafter named closure element toward thehereinafter named gasket by external fluid pressure upon such element, aclosure element received upon said shoulder and thus located forexposureto exterior pressure, such closure element and the hereafter namedgasket being peripherally encompassed by said casing above saidshoulder, a gasket received upon said shoulder betweenv the same andsaid element, and means exterior of said closure element and thusaccessible from the exterior of said casing, cooperable with saidclosure element for crowding said closure element toward said gasket andshoulder.

23. A bomb casing having an open end and interiorly shouldered adjacentsaid end, of a closure seated upon said shoulder and exposed to externalfluid pressure, means for securing the closure in place during normalhandling of the bomb, comprising means engaging the casing between theshoulder and the open end, a plate between the closure and the securingmeans, and a handle secured thereto for suspending the bomb.

JOHN B. McGAY. GEORGE E. NICHOLSON.

